Wiring an Outlet

By Dave Donovan

Most people get very nervous when it comes to electrical work, but you would be surprised at just how easy wiring an outlet can be. While basic home wiring is a safe do-it-yourself project if done properly, always keep in mind that if you don't know what you're doing, you could get injured. As with any job you undertake, safety is the number one priority. The mantra to a successful electrical repair or installation is - Respect the Electricity!


Today we're going to give you the information you need to install an electrical outlet to a circuit. Why would you want to? Well, there are a number of reasons. You may have a hallway where there is no outlet available and the vacuum cord isn't long enough to reach the end of it. You could have a bare corner of the room where you wanted to place the television or a lamp. Maybe you have a garage that's lacking outlets. Whatever the case, an additional outlet can come in pretty handy.
The difficulty of wiring an outlet depends on the location of the installation. If you want to install an electrical outlet on a different wall than the ones already existing, then it can prove a little more difficult than a straight shot. But, that's what we're here for. So, let's take a look at the tools and materials we'll need for basic home wiring.

Tools
•    Stud Finder
•    Volt-Ohm Meter
•    Drywall Saw
•    Pencil
•    Wire Strippers
•    Romex Stripper
•    Screwdrivers
•    Wire Fish
•    Drill with a Hole Bit
•    Measuring Tape
 
Materials
•    12/2 Romex Wire (depending on your household wiring)
•    Electrical Tape
•    Wire Nuts
•    Old-Work Outlet Box
•    Outlet and Cover
•    Joint Compound
•    Drop Cloth
•    Goggles and Face Mask
 
1. Pick where you want to install the electrical outlet and find the nearest existing outlet. Plug a lamp into it and go to the electrical panel to determine which breaker controls the circuit. Turn the breakers off individually until the light goes out. After you find the circuit, mark it in the panel box.

2. Unscrew and remove the panel cover. You'll have to make sure the breaker can handle the additional load you're planning to put on it. Be very careful here - the panel is still electrified. Set your Volt-Ohm Meter to AMPS and probe the wire attached to the breaker. (Depending on the type of meter, it may come with a clamp that clamps over the wire, or it may have a "U" shape that slides over the wire - check the instructions for your meter). Once you get the amperage, write it down and put the cover back on the panel. Now it's time for math.

3. To determine if the breaker can handle the extra load, you should have an idea of what the outlet will be used for. Whether it's for a TV, lamp, stereo, or vacuum, you will need to know the watts the equipment uses. Most vacuums have the amperage already labeled on them. Let's use a lamp for example. If the lamp is going to be using a 60 watt bulb, then to convert to amps, use the formula AMPS=WATTS/VOLTS. The volts number will be what the voltage is in your house, usually 120 volts. So, the equation will be AMPS=60/120. The answer is 0.5 amps. Now add that number to the amperage reading from the breaker and make sure it doesn't exceed 80 percent of the listed breaker rating. A 20 amp breaker shouldn't have more than 16 amps of load on it. Still with me? Good! Turn the breaker OFF and double check the circuit with the voltage tester.

4. Use the stud finder to locate all the wall studs between the new location and the nearest existing outlet. Mark them lightly with a pencil. Remove the cover and outlet from where you will be getting your feed. Next, use the tape measure to measure how far up the wall from the floor the other outlets in the room are. Measure and mark the new location to match.

5. Turn the old-work box around and place it against the wall where it will be going. Trace the box with the pencil. Put the goggles and face mask on and place the drop cloth down before you cut. Cut the drywall following the pencil lines with the drywall saw. Slide the old-work box in the opening to make sure it fits.

6. Find the previously marked studs and cut a square in the drywall so that the stud is exposed. Take the drill with the hole bit and drill through every stud between the new outlet and the one that's going to feed it.

7. Take the wire fish and run it through the holes, from one end to the other. Use the electrical tape to tape the romex wire to the wire fish and gently pull the wire fish back, bringing the romex wire with it.

8. Once you have the wire run from the new location to the feed outlet, cut the remaining wire off. Use the Romex stripper to make a cut in the plastic coating to expose the wires, about 12" worth. Slide the wires into the opening on the back of the old-work box. If you bought a plastic box, the connector is a pressure type; if it's a metal box, then you'll have to take a knockout out and tighten the connector down inside. Either way, make sure the connector is holding the romex at the place where the plastic coating is still on, NOT on the exposed wires. Push the old-work box back into the wall and tighten down the "wing" screws with a screwdriver.

9. With the box in the wall, cut any excess wire off. You should keep about 6" of wire in the box. Strip away about 3/4" of the insulation on the wires with the wire strippers. Depending on the outlet you purchased, it may have side screws to hold the wire or it may have holes on the back to pressure-hold them. The most secure way is with the side screws. The black wire gets connected to the copper, or the darker colored screw. The white wire gets connected to the silver, or the lighter colored screw. The ground gets connected to the green screw on the outlet. Once the wire is connected, wrap electrical tape around the outlet, covering the screws. Gently push the outlet back into the box and tighten the screws to hold it in place. Screw the cover on the outlet.

10. Back at the feed outlet, follow the same method of stripping the romex and its wires and connecting it to the box. Next, cut about 12" of romex from the coil, NOT the wall wire. Strip all the plastic coating away so you have individual wires. Strip 3/4" of the insulation on one end of all three wires. Take the exposed end of the black wire and connect it to the black wire that feeds the new outlet and the black wire that was feeding the existing outlet. Twist them together and tighten a wire nut over them. This is called a "pigtail." Follow that step with the white wires and the ground wires. Tape the wire nuts where the wires meet the nuts and carefully bend them back in the box. There should be a black, white, and ground wire hanging out of the box. Cut the wire back to about 6" and strip them as described before. Connect them to the outlet the same way as earlier. Don't forget to tape the outlet. Screw the outlet back onto the box and replace the cover.

11. Head back to the electrical panel and turn the breaker back on. Test both the new outlet and the feeding outlet with the voltage tester to make sure everything is wired correctly.
Once you check the electricity, and everything is OK, the only thing left to do is to clean up, replace the cut drywall squares and repair them with the joint compound, touch up the paint as needed and enjoy the satisfaction knowing that you accomplished wiring an outlet yourself.

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